Apparatus and method for manufacturing alternative combustion fuel for industrial boiler

ABSTRACT

Disclosed is an apparatus for manufacturing alternative combustion fuel for an industrial boiler, which is capable of easily forming an ionic bond between water and oil, of directly conducting a combustion process using a burner without the need for a preheating process to a predetermined temperature before the combustion, and of decreasing the discharge of air pollutants, such as sulfur gas, nitrogen gas, carbon monoxide, carbon dioxide, and dioxin.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus for manufacturing an alternative combustion fuel for an industrial boiler, and more particularly, to an apparatus for manufacturing an alternative combustion fuel for an industrial boiler, capable of easily forming an ionic bond between water and oil, of directly conducting a combustion process using a burner without the need for a preheating process to a predetermined temperature before the combustion, and of decreasing the discharge of air pollutants, such as sulfur gas, nitrogen gas, carbon monoxide, carbon dioxide, and dioxin.

2. Description of the Related Art

Typically, when various types of waste oil, waste edible oil, organic wastewater, plating wastewater, or dye wastewater, generated by industrial activity, are allowed to stand under natural conditions, they overflow due to rainwater, thus polluting soil, leading to environmental pollution. As well, such waste causes air pollution, attributed to combustion in the air.

Examples of such waste oil include waste engine oil or waste gear oil discharged from various vehicles and ships, waste transformer O.T. oil, waste cutting oil, waste rolling oil discharged from iron works, waste oil of petroleum sludge discharged from refinery works, waste edible oil of final sludge discharged from Ramen works, waste edible oil in sludge discharged upon the preparation of various edible oils, or final sludge discharged from soap works.

In the present invention, the term “waste oil” means waste engine oil or waste gear oil discharged from various vehicles and ships, waste transformer O.T. oil, waste cutting oil, waste rolling oil discharged from iron works, waste oil of petroleum sludge discharged from refinery works, waste edible oil of final sludge discharged from Ramen works, waste edible oil in sludge discharged upon the preparation of various edible oils, or final sludge discharged from soap works.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and an object of the present invention is to provide an apparatus and method for manufacturing an alternative combustion fuel for an industrial boiler, in which an ionic bond between water and oil can be easily formed.

Another object of the present invention is to provide an apparatus and method for manufacturing an alternative combustion fuel for an industrial boiler, in which a combustion process can be directly conducted using a burner without the need for a preheating process to a predetermined temperature before the combustion.

A further object of the present invention is to provide an apparatus and method for manufacturing an alternative combustion fuel for an industrial boiler, in which air pollutants, such as sulfur gas, nitrogen gas, carbon monoxide, carbon dioxide, and dioxin, can be discharged in smaller amounts.

In order to accomplish the above objects, the present invention provides an apparatus for manufacturing an alternative combustion fuel for an industrial boiler, comprising a first mixer for simultaneously receiving 2˜5 wt % of an inorganic salt composition, which is weighed using a first digital scale, from an inorganic salt composition tank having an inorganic salt composition stored therein by opening a first electronic valve, and receiving 95˜98 wt % of water, which is weighed using a second digital scale, from a water tank having water stored therein by opening a second electronic valve, and stirring them through rotation of a first impeller mounted to the shaft of a first geared motor according to operation of the first geared motor to form an emulsifier; a second mixer for simultaneously receiving 50.15˜67.85 wt % of a mixture of bunker C oil and waste oil, which is weighed using a third digital scale, from a bunker C oil and waste oil tank, including bunker C oil and waste oil mixed at a 1:1 ratio, by opening a third electronic valve, and receiving 12.60˜20.70 wt % of the emulsifier, which is weighed using a fourth digital scale, from the first mixer by opening a fourth electronic valve, and stirring them through rotation of a second impeller mounted to the shaft of a second geared motor at a predetermined rotation speed according to operation of the second geared motor to add the mixture of bunker C oil and waste oil with the emulsifier; a boiler for heating the mixture of bunker C oil and waste oil including the emulsifier, which is supplied from the second mixer through pumping of a first geared pump, to a predetermined temperature; a homogenizer for reducing water particles of the heated mixture of bunker C oil and waste oil including the emulsifier, which is supplied into an inlet of the homogenizer from the boiler through pumping of a first circulation pump, to a size of 1˜3 μm through rotation of a driven shaft of the homogenizer at a rotation speed of 1200˜1500 rpm, so as to ionically bond the water particles with the mixture of bunker C oil and waste oil; a third mixer for simultaneously receiving 62.75˜88.55 wt % of the mixture of bunker C oil and waste oil including the water particles ionically bonded therewith, from an outlet of the homogenizer through pumping of a second circulation pump and receiving 19.55˜29.15 wt % of a petroleum product and petrochemical product, which is weighed using a fifth digital scale, from a petroleum product and petrochemical product tank by opening a fifth electronic valve, and stirring them through rotation of a third impeller mounted to the shaft of a third geared motor according to the operation of the third geared motor to prepare an alternative combustion fuel for an industrial boiler; and a third geared pump for pumping the alternative combustion fuel for an industrial boiler from the third mixer into an alternative combustion fuel tank.

In addition, the present invention provides a method of manufacturing alternative combustion fuel for an industrial boiler, comprising an emulsifier formation step of simultaneously supplying 2˜5 wt % of an inorganic salt composition, which is weighed using a first digital scale, into a first mixer from an inorganic salt composition tank having an inorganic salt composition stored therein by opening a first electronic valve, and supplying 95˜98 wt % of water, which is weighed using a second digital scale, into the first mixer from a water tank by opening a second electronic valve, and stirring them through rotation of a first impeller mounted to the shaft of a first geared motor according to the operation of the first geared motor, thus forming an emulsifier; an emulsifier adding step of simultaneously supplying 50.15˜67.85 wt % of a mixture of bunker C oil and waste oil, which is weighed using a third digital scale, into a second mixer from a bunker C oil and waste oil tank including bunker C oil and waste oil mixed at a 1:1 ratio by opening a third electronic valve and supplying 12.60˜20.70 wt % of the emulsifier, which is weighed using a fourth digital scale, into the second mixer from the first mixer by opening a fourth electronic valve, and stirring them through rotation of a second impeller mounted to the shaft of a second geared motor at a predetermined rotation speed according to the operation of the second geared motor, thus adding the mixture of bunker C oil and waste oil with the emulsifier; a heating step of supplying the mixture of bunker C oil and waste oil including the emulsifier added in the emulsifier adding step into a boiler through pumping of a first geared pump so as to heat the mixture of bunker C oil and waste oil including the emulsifier to a predetermined temperature; an ionic bonding step of supplying the mixture of bunker C oil and waste oil including the emulsifier heated to the predetermined temperature in the heating step into an inlet of a homogenizer through pumping of a first circulation pump to reduce water particles thereof to a size of 1˜3 μm through rotation of a driven shaft of the homogenizer at a rotation speed of 1200˜1500 rpm, thus ionically bonding the water particles with the mixture of bunker C oil and waste oil; and an alternative combustion fuel preparation step of simultaneously supplying 62.75˜88.55 wt % of the mixture of bunker C oil and waste oil including the water particles tonically bonded therewith in the ionic bonding step into a third mixer from an outlet of the homogenizer through pumping of a second circulation pump and supplying 19.55˜29.15 wt % of a petroleum product and petrochemical product, which is weighed using a fifth digital scale, into the third mixer from a petroleum product and petrochemical product tank by opening a fifth electronic valve, and stirring them through rotation of a third impeller mounted to the shaft of a third geared motor according to the operation of the third geared motor, thus preparing an alternative combustion fuel for an industrial boiler.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a diagram schematically showing an apparatus for manufacturing an alternative combustion fuel for industrial boilers, according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, a detailed description will be given of an apparatus for manufacturing an alternative combustion fuel for an industrial boiler according to the present invention, with reference to the appended drawing.

FIG. 1 is a view schematically showing the apparatus for manufacturing an alternative combustion fuel for an industrial boiler, according to the present invention.

As shown in FIG. 1, the apparatus for manufacturing an alternative combustion fuel for an industrial boiler, according to the present invention, comprises a first mixer 20 for simultaneously receiving 2˜5 wt % of an inorganic salt composition, as weighed using a first digital scale 12, from an inorganic salt composition tank 11 having an inorganic salt composition stored therein by opening a first electronic valve 13, and receiving 95˜98 wt % of water (H₂O), as weighed using a second digital scale 15, from a water tank 14 having water stored therein by opening a second electronic valve 16, and stirring them through the rotation of a first impeller 18 mounted to the shaft of a first geared motor 17 according to the operation of the first geared motor 17 to form an emulsifier, and a second mixer 30 for simultaneously receiving 50.15˜67.85 wt % of a mixture of bunker C oil and waste oil, as weighed using a third digital scale 22, from a bunker C oil and waste oil tank 21 including bunker C oil and waste oil mixed at a 1:1 ratio by opening a third electronic valve 23, and receiving 12.60˜20.70 wt % of the emulsifier, as weighed using a fourth digital scale 24, from the first mixer 20 by opening a fourth electronic valve 25, and stirring them through the rotation of a second impeller 27 mounted to the shaft of a second geared motor 26 at a predetermined rotation speed according to the operation of the second geared motor 26 to add the emulsifier to the mixture of bunker C oil and waste oil. In addition, the apparatus of the present invention comprises a boiler 40 (or a heater) for heating the mixture of bunker C oil and waste oil including the emulsifier, which is supplied from the second mixer 30 through pumping of a first geared pump 32, to a predetermined temperature (e.g., 70˜90° C.), and a homogenizer 50 for reducing water particles of the heated mixture of bunker C oil and waste oil including the emulsifier, which is supplied into the inlet 50 a of the homogenizer 50 from the boiler 40 by the pumping of a first circulation pump 42, to a size of 1˜3 μm so as to ionically bond them with the oil mixture. Further, the apparatus of the present invention includes a third mixer 60 for simultaneously receiving 62.75˜88.55 wt % of the mixture of bunker C oil and waste oil including the water particles ionically bonded therewith (which is referred to as “emulsified oil”), from the outlet 57 of the homogenizer 50 by the pumping of a second circulation pump 62, and receiving 19.55˜29.15 wt % of a petroleum product and petrochemical product, as weighed using a fifth digital scale 72, from a petroleum product and petrochemical product tank 70 by opening a fifth electronic valve 74, and stirring them through the rotation of a third impeller 66 mounted to the shaft of a third geared motor 64 according to the operation of the third geared motor 64 to prepare an alternative combustion fuel for an industrial boiler. Also, a third geared pump 80 for pumping the alternative combustion fuel for an industrial boiler into an alternative combustion fuel tank 90 from the third mixer 60 is included.

In the present invention, the homogenizer 50 is composed of a drive motor 51, a drive pulley 52 rotatably mounted to the shaft 51 a of the drive motor 51, a driven pulley 53 rotating in response to rotation force of the drive motor 51 transferred via a belt 52 a, a driven shaft 54 having a screw conveyor 54 a mounted on the outer surface thereof while rotatably supporting the driven pulley 53 at 1200˜1800 rpm so as to discharge and transfer the mixture of bunker C oil and waste oil including the emulsifier, which is heated to the predetermined temperature (e.g., 70˜90° C.) and supplied into the inlet 50 a through the operation of the first circulation pump 42, a tapered shaft support 55 for supporting the outer surface of a tapered head 54 b formed at the front end of the driven shaft 54, and an outlet 57 for discharging the alternative combustion fuel for an industrial boiler, in which water particles reduced to a size of 1˜3 μm are ionically bonded with the mixture of bunker C oil and waste oil while passing through the gap 56 (e.g., 1˜2 mm gap) between the outer surface of the tapered head 54 b of the driven shaft 54 and the inner surface of the shaft support 55. In addition, the homogenizer 50 includes a gap control member 58 threadably mounted on the outer surface of the driven shaft 54 for decreasing or increasing the gap between the outer surface of the tapered head 54 b of the driven shaft 54 and the inner surface of the shaft support 55 through clockwise or counterclockwise rotation thereof, and a cylindrical housing 59 for accommodating the screw conveyor 54 a mounted on the outer surface of the driven shaft 54.

In FIG. 1, reference number 44 designates a thermometer for measuring the temperature of the mixture of bunker C oil and waste oil including the emulsifier heated in the boiler 40.

In the present invention, the inorganic salt composition includes sodium carbonate (Na₂CO₃), sodium chloride (NaCl), sodium bicarbonate (NaHCO₃), magnesium chloride (MgCl₂), and calcium chloride (CaCl₂). The inorganic salt composition solution comprising the inorganic salt composition and water (H₂O) is basic, and the mixture of bunker C oil and waste oil has higher fatty acid esters therein. Thus, when the mixture of bunker C oil and waste oil and the inorganic salt composition solution are rapidly rotated at 400˜7000 rpm, they are emulsified by the production of an alkali metal salt, and therefore the ionically bonded state between water and salt is maintained, resulting in the prevention of oil-water separation.

The inorganic salt composition used in the present invention satisfies the requirements for emulsion fuel through the following mechanism.

Na₂CO₃, which is one component of the inorganic salt composition, reacts with water, thus producing aqueous NaOH:

Na₂CO₃+2H₂O→2NaOH+H₂CO₃.

In addition, such basic aqueous NaOH reacts with alkali earth metal chloride, that is, MgCl₂ and CaCl₂, in an aqueous phase:

2NaOH+MgCl₂→Mg(OH)₂+2NaCl₂

NaOH+CaCl₂→Ca(OH)₂+2NaCl.

Further, upon the above reaction, MgCl₂ and CaCl₂ participate in another reaction:

2Na₂CO₃+MgCl₂+CaCl₂═MgCO₃+CaCO₃+4NaCl.

Accordingly, when the chloride and waste oil are rotated at 80˜90° C. at 400˜7000 rpm, the higher fatty acid ester component of the waste oil or waste edible oil is hydrolyzed, producing a higher fatty acid sodium salt:

(wherein R, R′, R″ are each a higher alkyl group).

The higher fatty acid sodium salt produced through the above reaction exhibits the function as the emulsifier, such that the added water and the mixture of bunker C oil and waste oil are emulsified, in which the dispersed water particles having a size of about 1˜4 μm are surrounded by oil. Ultimately, oil-water separation does not occur even after storage for a long time, thanks to the ionic bond therebetween.

In this way, in the present invention, since no oil-water separation between water and the mixture of bunker C oil and waste oil occurs when using the inorganic salt composition, a mixture comprising low-sulfur bunker C oil and waste oil may serve as emulsion fuel.

Further, the alternative fuel thus obtained may be applied to baths, cogeneration plants, heating power plants, the ceramic production field, the cement manufacturing field, and other industrial works.

A better understanding of the present invention may be obtained in light of the following examples, concerning the method of manufacturing the alternative combustion fuel for an industrial boiler, which are set forth to illustrate, but are not to be construed to limit the present invention.

EXAMPLE 1

An inorganic salt composition was supplied into a first mixer 20 in an amount of 5 wt %, weighed using a first digital scale 12, from an inorganic salt composition tank 11 having an inorganic salt composition stored therein by opening a first electronic valve 13. Simultaneously, water was supplied into the first mixer 20 in an amount of 95 wt %, weighed using a second digital scale 15, from a water tank 14 by opening a second electronic valve 16, and the inorganic salt composition and water were stirred by rotating a first impeller 18 mounted to the shaft of a first geared motor 17 in response to the operation of the first geared motor 17, yielding an emulsifier (an emulsifier formation process). Thereafter, a mixture of bunker C oil and waste oil was supplied into a second mixer 30 in an amount of 67.85 wt %, weighed using a third digital scale 22, from a bunker C oil and waste oil tank 21, including bunker C oil and waste oil mixed at a 1:1 ratio, by opening a third electronic valve 23. Simultaneously, the emulsifier obtained in the emulsifier formation process was supplied into the second mixer 30 in an amount of 12.60 wt %, weighed using a fourth digital scale 24, from the first mixer 20 by opening a fourth electronic valve 25, and the mixture of bunker C oil and waste oil was added with the emulsifier (emulsifier adding process) while stirring them by rotating a second impeller 27 mounted to the shaft of a second geared motor 26 at a predetermined rotation speed (e.g., 100˜300 rpm) for 10˜20 min in response to the operation of the second geared motor 26. Subsequently, the mixture of bunker C oil and waste oil, including the emulsifier added in the emulsifier adding process, was supplied into a boiler 40 through pumping of a first geared pump 32 to heat it to a predetermined temperature (e.g., 70˜90° C.) (heating process). Thereafter, the mixture of bunker C oil and waste oil including the emulsifier, heated to the predetermined temperature in the heating process, was supplied into the inlet 50 a of a homogenizer 50 through pumping of a first circulation pump 42, and the driven shaft 54 of the homogenizer 50 was rotated at a rotation speed of 1200˜1500 rpm such that the water particles thereof were reduced to a size of 1˜3 μm to ionically bond them with the oil mixture (ionic bonding process), finally discharging the resultant oil mixture through the outlet 57 of the homogenizer 50.

The mixture of bunker C oil and waste oil including the water particles ionically bonded therewith in the ionic bonding process, which is referred to as emulsified oil, was supplied into a third mixer 60 in an amount of 80.45 wt % from the outlet 57 of the homogenizer 50 through pumping of a second circulation pump 62. Simultaneously, a petroleum product and petrochemical product was supplied into the third mixer 60 in an amount of 19.55 wt %, weighed using a fifth digital scale 72, from a petroleum product and petrochemical product tank 70 by opening a fifth electronic valve 74. Thereafter, a stirring process was conducted by rotating a third impeller 66 mounted to the shaft of a third geared motor 64 in response to the operation of the third geared motor 64, resulting in an alternative combustion fuel for an industrial boiler (alternative fuel production process). The alternative combustion fuel thus obtained was then pumped into an alternative fuel tank 90 through the operation of a third geared pump 80.

In the homogenizer 50, the rotation force of the drive motor 51 was transferred to the driven shaft 54 via a drive pulley 52 rotatably mounted to the shaft 51 a of the drive motor 51, a belt 52 a or chain, and a driven pulley 53, thereby rotating the driven shaft 54.

Accordingly, while a screw conveyor 54 a mounted on the outer surface of the driven shaft 54 and accommodated in the housing 59 was rotated in response to the rotation of the driven shaft 54, the mixture of bunker C oil and waste oil including the emulsifier, supplied into the inlet 50 a of the homogenizer 50 through the operation of the first circulation pump 42, was ionically bonded with the reduced water particles thereof and then discharged through the outlet 57 of the homogenizer 50.

That is, the mixture of bunker C oil and waste oil, having water particles reduced to a size of 1˜3 μm and ionically bonded therewith, was discharged through the outlet 57 of the homogenizer 50 while passing through the gap 56 between the outer surface of the tapered head 54 b of the driven shaft 54 and the inner surface of the shaft support 55.

Using a gap control member threadably mounted on the outer surface of the driven shaft 54 for decreasing or increasing the gap between the outer surface of the tapered head 54 b of the driven shaft 54 and the inner surface of the shaft support 55 through the clockwise or counterclockwise rotation thereof, the size of water particles could be further decreased or increased.

The alternative combustion fuel for an industrial boiler prepared in Example 1 was tested as follows by Korea Petroleum Quality Institute.

In order to evaluate the storage stability of the alternative combustion fuel for an industrial boiler prepared in Example 1, 90 days after such preparation, an oil-water separation test was conducted using a wet process (1 L of a sample was taken and compared with respect to the properties of the upper layer and the lower layer thereof at 20° C. at 10-day intervals) or an infrared spectrometric process (simulating conditions similar to the wet process to obtain the same test result). As a result, no oil-water separation was observed.

In addition, the moisture in the alternative combustion fuel for an industrial boiler prepared in Example 1 was measured to be 1.40 vol % according to KSM ISO 3733, sulfur therein to be 0.12 wt % according to ASTM D 1552, ash therein to be 0.018 wt % according to KSM ISO 6245, and precipitate therein to be 0.17 wt % according to KSM ISO 3735. Further, according to inductively coupled plasma emission spectroscopy, serving as a waste process test, cadmium (Cd) and compounds thereof were not detected, chromium (Cr) and compounds thereof were detected in an amount of 0.79 mg/L, lead (Pb) and compounds thereof were detected in an amount of 0.73 mg/L, and arsenic (As) and compounds thereof were detected in an amount of 0.88 mg/L.

Moreover, in order to analyze the amounts of discharge gases and dusts discharged upon combustion, the amounts of carbon monoxide (CO), carbon dioxide (CO₂), nitrogen gas (NO), sulfur gas (SO₂), and dioxin were measured using a flue gas analyzer (CGA-520), available from Okhang Gas Analysis Co. Ltd., Korea. As a result, carbon monoxide was detected at a level of 30 ppm, carbon dioxide at 10 ppm, nitrogen oxide at 23 ppm, sulfur gas at 25 ppm, and dioxin at 0.047 ppm. The heat value was 9,250 cal/g.

EXAMPLE 2

The inorganic salt composition was supplied into the first mixer 20 in an amount of 3 wt %, weighed using the first digital scale 12, from the inorganic salt composition tank 11 having an inorganic salt composition stored therein by opening the first electronic valve 13. Simultaneously, water was supplied into the first mixer 20 in an amount of 97 wt %, weighed using the second digital scale 15, from the water tank 14 by opening the second electronic valve 16, and the inorganic salt composition and water were stirred by rotating the first impeller 18 mounted to the shaft of the first geared motor 17 in response to the operation of the first geared motor 17, yielding an emulsifier (an emulsifier formation process). Thereafter, the mixture of bunker C oil and waste oil was supplied into the second mixer 30 in an amount of 59 wt %, weighed using the third digital scale 22, from the bunker C oil and waste oil tank 21, including bunker C oil and waste oil mixed at a 1:1 ratio, by opening the third electronic valve 23. Simultaneously, the emulsifier was supplied into the second mixer 30 in an amount of 18 wt %, weighed using the fourth digital scale 24, from the first mixer 20 by opening the fourth electronic valve 25, and the mixture of bunker C oil and waste oil was added with the emulsifier (emulsifier adding process) while stirring them by rotating the second impeller 27 mounted to the shaft of the second geared motor 26 at a predetermined rotation speed (e.g., 100˜300 rpm) for 10˜20 min in response to operation of the second geared motor 26. Subsequently, the mixture of bunker C oil and waste oil including the emulsifier was charged into the boiler 40 from the second mixer 30 through pumping of the first geared pump 32 to heat it to a predetermined temperature (e.g., 70˜90° C.) (heating process). Thereafter, the mixture of bunker C oil and waste oil including the emulsifier, heated to the predetermined temperature in the heating process, was supplied into the inlet 50 a of the homogenizer 50 through pumping of the first circulation pump 42, and the driven shaft 54 was rotated at 1200˜1500 rpm such that the water particles thereof were reduced to a size of 1˜3 μm to ionically bond them with the oil mixture (ionic bonding process), finally discharging the resulting oil mixture through the outlet 57 of the homogenizer 50.

The mixture of bunker C oil and waste oil including the water particles tonically bonded therewith in the ionic bonding process, which is referred to as emulsified oil, was supplied into the third mixer 60 in an amount of 77 wt % from the outlet 57 of the homogenizer 50 through pumping of the second circulation pump 62. Simultaneously, the petroleum product and petrochemical product was supplied into the third mixer 60 in an amount of 23 wt %, weighed using the fifth digital scale 72, from the petroleum product and petrochemical product tank 70 by opening the fifth electronic valve 74. Thereafter, a stirring process was conducted by rotating the third impeller 66 mounted to the shaft of the third geared motor 64 in response to the operation of the third geared motor 64, thus producing an alternative combustion fuel for an industrial boiler (alternative fuel production process), which was then pumped into the alternative combustion fuel tank 90 through the operation of the third geared pump 80.

The alternative combustion fuel for an industrial boiler prepared in Example 2 was tested as follows by Korea Petroleum Quality Institute.

In order to evaluate the storage stability of the alternative combustion fuel for an industrial boiler, prepared in Example 2, 90 days after such preparation, an oil-water separation test was conducted using a wet process (1 L of a sample was taken and compared with respect to the properties of the upper layer and the lower layer thereof at 20° C. at 10-day intervals) and an infrared spectrometric process (simulating conditions similar to the wet process to obtain the same test result). As a result, no oil-water separation was observed.

In addition, the moisture in the alternative combustion fuel for an industrial boiler prepared in Example 2 was measured to be 1.45 vol % according to KSM ISO 3733, sulfur therein to be 0.14 wt % according to ASTM D 1552, ash therein to be 0.023 wt % according to KSM ISO 6245, and precipitate therein to be 0.18 wt % according to KSM ISO 3735. Further, according to inductively coupled plasma emission spectroscopy, serving as a waste process test, cadmium (Cd) and compounds thereof were not detected, chromium (Cr) and compounds thereof were detected in an amount of 0.75 mg/L, lead (Pb) and compounds thereof were detected in an amount of 0.72 mg/L, and arsenic (As) and compounds thereof were detected in an amount of 0.63 mg/L.

Also, in order to analyze the amounts of discharge gases and dusts discharged upon combustion, the amounts of carbon monoxide (CO), carbon dioxide (CO₂), nitrogen gas (NO), sulfur gas (SO₂), and dioxin were measured using a flue gas analyzer (CGA-520), available from Okhang Gas Analysis Co. Ltd., Korea. As a result, carbon monoxide was detected at a level of 28 ppm, carbon dioxide at 15 ppm, nitrogen oxide at 25 ppm, sulfur gas at 27 ppm, and dioxin at 0.043 ppm. The heat value was 9,575 cal/g.

EXAMPLE 3

The inorganic salt composition was supplied into the first mixer 20 in an amount of 2 wt %, weighed using the first digital scale 12, from the inorganic salt composition tank 11 having an inorganic salt composition stored therein by opening the first electronic valve 13. Simultaneously, water was supplied into the first mixer 20 in an amount of 98 wt %, weighed using the second digital scale 15, from the water tank 14 by opening the second electronic valve 16, and thus the inorganic salt composition and water were stirred by rotating the first impeller 18 mounted to the shaft of the first geared motor 17 in response to the operation of the first geared motor 17, yielding an emulsifier (an emulsifier formation process). Thereafter, the mixture of bunker C oil and waste oil was supplied into the second mixer 30 in an amount of 50.15 wt %, weighed using the third digital scale 22, from the bunker C oil and waste oil tank 21, including bunker C oil and waste oil mixed at 1:1, by opening the third electronic valve 23. Simultaneously, the emulsifier was supplied into the second mixer 30 in an amount of 20.70 wt %, weighed using the fourth digital scale 24, from the first mixer 20 by opening the fourth electronic valve 25, and thus the mixture of bunker C oil and waste oil was added with the emulsifier (emulsifier adding process) while stirring them through the rotation of the second impeller 27 mounted to the shaft of the second geared motor 26 at a predetermined rotation speed (e.g., 100˜300 rpm) for 10˜20 min in response to the operation of the second geared motor 26. Subsequently, the mixture of bunker C oil and waste oil including the emulsifier was supplied into the boiler 40 from the second mixer 30 through pumping of the first geared pump 32 to heat it to a predetermined temperature (e.g., 70˜90° C.) (heating process). Thereafter, the mixture of bunker C oil and waste oil including the emulsifier, heated to the predetermined temperature in the heating process, was supplied into the inlet 50 a of the homogenizer 50 through pumping of the first circulation pump 42, and the driven shaft 54 was rotated at 1200˜1500 rpm such that the water particles thereof were reduced to a size of 1˜3 μm to ionically bond them with the oil mixture (ionic bonding process), finally discharging the resulting oil mixture through the outlet 57 of the homogenizer 50.

The mixture of bunker C oil and waste oil including the water particles ionically bonded therewith in the ionic bonding process, which is referred to as emulsified oil, was supplied into the third mixer 60 in an amount of 70.85 wt % from the outlet 57 of the homogenizer 50 through pumping of the second circulation pump 62. Simultaneously, the petroleum product and petrochemical product were supplied into the third mixer 60 in an amount of 29.15 wt %, weighed using the fifth digital scale 72, from the petroleum product and petrochemical product tank 70 by opening the fifth electronic valve 74. Thereafter, a stirring process was conducted through the rotation of the third impeller 66 mounted to the shaft of the third geared motor 64 in response to the operation of the third geared motor 64, therefore producing an alternative combustion fuel for an industrial boiler (alternative fuel production process), which was then pumped into the alternative fuel tank 90 through the operation of the third geared pump 80.

The alternative combustion fuel for an industrial boiler prepared in Example 3 was tested as follows by Korea Petroleum Quality Institute.

In order to evaluate the storage stability of the alternative combustion fuel for an industrial boiler prepared in Example 3, 90 days after such preparation, an oil-water separation test was conducted using a wet process (1 L of a sample was taken and compared with respect to the properties of the upper layer and the lower layer thereof at 20° C. at 10-day intervals) or an infrared spectrometric process (simulating conditions similar to the wet process to obtain the same test result). As a result, no oil-water separation was observed.

In addition, the moisture in the alternative combustion fuel for an industrial boiler prepared in Example 2 was measured to be 1.35 vol % according to KSM ISO 3733, sulfur therein to be 0.15 wt % according to ASTM D 1552, ash therein to be 0.017 wt % according to KSM ISO 6245, and precipitate therein to be 0.16 wt % according to KSM ISO 3735. Further, according to inductively coupled plasma emission spectroscopy, serving as a waste process test, cadmium (Cd) and compounds thereof were not detected, chromium (Cr) and compounds thereof were detected in an amount of 0.66 mg/L, lead (Pb) and compounds thereof were detected in an amount of 0.65 mg/L, and arsenic (As) and compounds thereof were detected in an amount of 0.55 mg/L.

Moreover, in order to analyze the amounts of discharge gases and dusts discharged upon combustion, the amounts of carbon monoxide (CO), carbon dioxide (CO₂), nitrogen gas (NO), sulfur gas (SO₂), and dioxin were measured using a flue gas analyzer (CGA-520), available from Okhang Gas Analysis Co. Ltd., Korea. As a result, carbon monoxide was detected at a level of 25 ppm, carbon dioxide at 18 ppm, nitrogen oxide at 20 ppm, sulfur gas at 10 ppm, and dioxin at 0.045 ppm. The heat value was 10,575 cal/g.

In the present invention, the term “waste oil” means waste engine oil discharged from various vehicles and ships, waste gear oil discharged from various vehicles and ships, waste transformer O.T. oil, waste cutting oil, waste rolling oil discharged from iron works, waste oil of petroleum sludge discharged from refinery works, waste edible oil of final sludge discharged from Ramen works, waste edible oil in sludge discharged upon the preparation of various edible oils, and final sludge discharged from soap works.

Examples of the petroleum product and petrochemical product include thinner, toluene, methylalcohol, propylene, isopropylalcohol, polybutene, benzene, xylene, naphthalene, etc.

In the preparation of the emulsifier, when the inorganic salt composition is contained in an amount exceeding 5 wt %, the ionic bond formation rate is increased but the color of the alternative combustion fuel for an industrial boiler of the present invention is undesirably changed to brown. On the other hand, when the inorganic salt composition is contained in an amount less than 2 wt %, the ionic bond formation rate is decreased, undesirably reducing the workability. In addition, when water is contained in an amount exceeding 98 wt %, the ionic bonds cannot be formed and the color of the alternative combustion fuel for an industrial boiler of the present invention is undesirably changed to brown.

Additionally, when the mixture of bunker C oil and waste oil is contained in an amount exceeding 67.85 wt %, the heat value is decreased and thus the amount of petroleum product and petrochemical product is increased, unfavorably increasing the preparation cost. On the other hand, when the mixture of bunker C oil and waste oil is contained in an amount less than 50.15 wt %, the heat value is increased but air pollution results from incomplete combustion. Furthermore, when the emulsifier is contained in an amount exceeding 20.70 wt %, the color of the alternative combustion fuel for an industrial boiler of the present invention is undesirably changed to brown. On the other hand, when the emulsifier is contained in an amount less than 12.60 wt %, it is only weakly ionically bonded with the mixture of bunker C oil and waste oil, thus undesirably reducing the workability. Moreover, when the amount of petroleum product and petrochemical product exceeds 29.15 wt %, the heat value is increased but the preparation cost is also undesirably increased. On the other hand, when the amount of petroleum product and petrochemical product is less than 19.55 wt %, the heat value is decreased and thus it is impossible to conduct a spray process using a burner, which is not shown, and furthermore, air pollution is caused.

In the present invention, the mixture of bunker C oil and waste oil mixed at 1:1 is added with the emulsifier, and then mixed with the petroleum product and petrochemical product to increase the heat value, thus producing the alternative combustion fuel for an industrial boiler. However, the present invention is not limited thereto. For example, the bunker C oil is mixed with the emulsifier, and then further mixed with the petroleum product and petrochemical product to increase the heat value, thus producing the alternative combustion fuel for an industrial boiler, which is included in the scope of the present invention.

As described hereinbefore, the present invention provides an apparatus and method for manufacturing an alternative combustion fuel for an industrial boiler. According to the present invention, an ionic bond between water and oil can be easily formed, and also a combustion process can be directly conducted using a burner without the need for a preheating process before the combustion. Further, the discharge of air pollutants, such as sulfur gas, nitrogen gas, carbon monoxide, carbon dioxide and dioxin, can be decreased.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

1. An apparatus for manufacturing an alternative combustion fuel for an industrial boiler, comprising: a first mixer for simultaneously receiving 2˜5 wt % of an inorganic salt composition, which is weighed using a first digital scale, from an inorganic salt composition tank having an inorganic salt composition stored therein by opening a first electronic valve, and receiving 95˜98 wt % of water, which is weighed using a second digital scale, from a water tank having water stored therein by opening a second electronic valve, and stirring them through rotation of a first impeller mounted to the shaft of a first geared motor according to operation of the first geared motor to form an emulsifier; a second mixer for simultaneously receiving 50.15˜67.85 wt % of a mixture of bunker C oil and waste oil, which is weighed using a third digital scale, from a bunker C oil and waste oil tank, including bunker C oil and waste oil mixed at a 1:1 ratio, by opening a third electronic valve, and receiving 12.60˜20.70 wt % of the emulsifier, which is weighed using a fourth digital scale, from the first mixer by opening a fourth electronic valve, and stirring them through rotation of a second impeller mounted to the shaft of a second geared motor at a predetermined rotation speed according to operation of the second geared motor to add the mixture of bunker C oil and waste oil with the emulsifier; a boiler for heating the mixture of bunker C oil and waste oil including the emulsifier, which is supplied from the second mixer through pumping of a first geared pump, to a predetermined temperature; a homogenizer for reducing water particles of the heated mixture of bunker C oil and waste oil including the emulsifier, which is supplied into an inlet of the homogenizer from the boiler through pumping of a first circulation pump, to a size of 1˜3 μm through rotation of a driven shaft of the homogenizer at a rotation speed of 1200˜1500 rpm, so as to ionically bond the water particles with the mixture of bunker C oil and waste oil; a third mixer for simultaneously receiving 62.75˜88.55 wt % of the mixture of bunker C oil and waste oil including the water particles tonically bonded therewith, from an outlet of the homogenizer through pumping of a second circulation pump and receiving 19.55˜29.15 wt % of a petroleum product and petrochemical product, which is weighed using a fifth digital scale, from a petroleum product and petrochemical product tank by opening a fifth electronic valve, and stirring them through rotation of a third impeller mounted to the shaft of a third geared motor according to the operation of the third geared motor to prepare an alternative combustion fuel for an industrial boiler; and a third geared pump for pumping the alternative combustion fuel for an industrial boiler from the third mixer into an alternative combustion fuel tank.
 2. The apparatus as set forth in claim 1, wherein the homogenizer comprises a drive motor, a drive pulley rotatably mounted to a shaft of the drive motor, a driven pulley rotating in response to rotation force of the drive motor transferred through a belt, a driven shaft having a screw conveyor mounted on an outer surface thereof while rotatably supporting the driven pulley so as to discharge and transfer the mixture of bunker C oil and waste oil including the emulsifier, which is heated to a predetermined temperature and supplied into the inlet of the homogenizer through the operation of the first circulation pump, a tapered shaft support for supporting an outer surface of a tapered head formed at a front end of the driven shaft, an outlet for discharging the alternative combustion fuel for an industrial boiler in which water particles reduced to a size of 1˜3 μm are ionically bonded with the mixture of bunker C oil and waste oil while passing through a gap between the outer surface of the tapered head of the driven shaft and an inner surface of the shaft support, a gap control member threadably mounted on the outer surface of the driven shaft for decreasing or increasing the gap between the outer surface of the tapered head of the driven shaft and the inner surface of the shaft support through clockwise or counterclockwise rotation thereof, and a cylindrical housing for accommodating the screw conveyor mounted on the outer surface of the driven shaft.
 3. The apparatus as set forth in claim 1, wherein the inorganic salt composition comprises sodium carbonate, sodium chloride, sodium bicarbonate, magnesium chloride, and calcium chloride.
 4. A method of manufacturing alternative combustion fuel for an industrial boiler, comprising: an emulsifier formation step of simultaneously supplying 2˜5 wt % of an inorganic salt composition, which is weighed using a first digital scale, into a first mixer from an inorganic salt composition tank having an inorganic salt composition stored therein by opening a first electronic valve, and supplying 95˜98 wt % of water, which is weighed using a second digital scale, into the first mixer from a water tank by opening a second electronic valve, and stirring them through rotation of a first impeller mounted to the shaft of a first geared motor according to the operation of the first geared motor, thus forming an emulsifier; an emulsifier adding step of simultaneously supplying 50.15˜67.85 wt % of a mixture of bunker C oil and waste oil, which is weighed using a third digital scale, into a second mixer from a bunker C oil and waste oil tank including bunker C oil and waste oil mixed at a 1:1 ratio by opening a third electronic valve and supplying 12.60˜20.70 wt % of the emulsifier, which is weighed using a fourth digital scale, into the second mixer from the first mixer by opening a fourth electronic valve, and stirring them through rotation of a second impeller mounted to the shaft of a second geared motor at a predetermined rotation speed according to the operation of the second geared motor, thus adding the mixture of bunker C oil and waste oil with the emulsifier; a heating step of supplying the mixture of bunker C oil and waste oil including the emulsifier added in the emulsifier adding step into a boiler through pumping of a first geared pump so as to heat the mixture of bunker C oil and waste oil including the emulsifier to a predetermined temperature; an ionic bonding step of supplying the mixture of bunker C oil and waste oil including the emulsifier heated to the predetermined temperature in the heating step into an inlet of a homogenizer through pumping of a first circulation pump to reduce water particles thereof to a size of 1˜3 μm through rotation of a driven shaft of the homogenizer at a rotation speed of 1200˜1500 rpm, thus ionically bonding the water particles with the mixture of bunker C oil and waste oil; and an alternative combustion fuel preparation step of simultaneously supplying 62.75˜88.55 wt % of the mixture of bunker C oil and waste oil including the water particles ionically bonded therewith in the ionic bonding step into a third mixer from an outlet of the homogenizer through pumping of a second circulation pump and supplying 19.55˜29.15 wt % of a petroleum product and petrochemical product, which is weighed using a fifth digital scale, into the third mixer from a petroleum product and petrochemical product tank by opening a fifth electronic valve, and stirring them through rotation of a third impeller mounted to the shaft of a third geared motor according to the operation of the third geared motor, thus preparing an alternative combustion fuel for an industrial boiler. 